Grenade launching arrangement



y 1967 R" BARR 3,31%,Q33

GRENADE LAUNCHING ARRANGEMENT Filed Sept. 29, 1965 2 Sheets-$heet 1lRl/V/A/ R BAR/P INVENTOR May 9, 1967 R. BARR 9 13 GRENADE LAUNCHINGARRANGEMENT Filed Sept. 29, 1965 2 Sheets-Sheet 5' 7 HI H '7 5. 5' N m'1 2 y I 1,; uni: 7 I l [will hill r1, I f I I! {1 w my:

I/PW/Al R. BAR/F INVENTOR States atent Patented May 9, 1%67 3,318,033LAUNQHHNG llrwin R. Barr, Lutherville, Md, assignor to AAl Corpo=ration, Cocheysville, Md, a corporation of Maryland Filed Sept. 29,1965, Ser. No. 491,399 ill Cl. 42-41) This invention relates to grenadelaunchers, and more particularly to an adapter arrangement for enablingthe firing of relatively large diameter grenades from a standard singlebarrel shotgun, such as a riot type shotgun.

In the standard riot type shotgun there is employed a conventionaltrigger firing mechanism, firing chamber and barrel, the gun beingadapted to accept gas-generating blank or other desired shotgun shells.The present invention is adapted for launching a grenade with the aid ofsuch a shotgun while employing a blank gas-generating cartridge. As thebarrel of such shotguns, as well as other conventional shotguns, is notitself suitable for launching of a rifled grenade with a grenade releasehandle, it is highly desirable to provide an arrangement which willenable the launching of such grenades when such are desired to be used,while still enabling the riot shotgun to be used in its normal fashionby a simple change.

It is accordingly an object and feature of this invention to provide agrenade adapter which will enable the launching of relatively largediameter grenades having external rifiing thereon and a release handle.

It is still a further feature of this invention to provide a grenadelaunching system which will enable the grenade to be launched with spinimparted thereto for accuracy, While also self-releasing the grenadehandle as a function of the launching, the grenade firing mechanismbeing thereby actuated to initiate a firing sequence which will resultin subsequent delayed firing of the grenade charge at some point distantfrom the launching zone.

Still other objects, features and attendant advantages will becomeapparent to those skilled in the art from a reading of the followingdetailed description of one preferred embodiment constructed inaccordance with the invention, taken in conjunction with theaccompanying drawings wherein:

FIGURE 1 is an exploded view of a shotgun, adapter and grenade accordingto the invention,

FIGURE 2 is a partial longitudinal section view of the front end of thebarrel of the gun, with the grenade adapter secured in place,

FIGURE 3 is a cross-section vieW taken on the line 3-3 of FIGURE 2,

FIGURE 4 is a longitudinal section view of the front end of the gunbarrel and the grenade adapter, and showing a grenade in placepreparatory to launching, the grenade being broken away in part forclarity of illustration,

FIGURE 5 is a View of the gun, adapter and grenade assembly,illustrating the grenade shortly after launching.

Referring now in detail to the figures of the drawing, in FIGURE 1 thereis shown in exploded view a grenade adapter 11 which is adapted to fitover the muzzle end of the barrel 43 of a standard riot shotgun illhaving a conventional firing mechanism, firing chamber and barrel. Thegrenade adapter is constructed to enable the launching of a grenade 51having a rifled band 53 at one end thereof and a release handle 55 atthe other end and extending along one side of the grenade body.

As seen in FIGURE 2, the grenade adapter it includes a closed base endit? which terminates in a split-clamp 15 adapted to fit over the muzzleend of barrel 43, being clamped in place by an adjustment screw 21extending through a pair of spaced apertured wings 19a, 1% at theslotted upper side of the split clamp. Preferably, the

aperture of one wing 19b is threaded, and the other aperture unthreadedto enable facile tightening of the adjustment screw 21 withoutnecessitating the employment of a securing nut, although a securing nutor other tightening means may of course be employed if so desired. Itwill be appreciated that the slot formed between the two upstandingwings 19a, 1% will readily accommodate the sight bead whichconventionally is located at the muzzle end of the barrel.

The adapter ll is seated in place over the barrel 43, with the end ofthe barrel abutting against a shoulder stop 17 at the inner end of theclamp 15.

A central bore 23 is formed in the base 13 of the adapter, this borebeing preferably of the same size as the bore of the barrel 43, andbeing coaxial therewith. The base 13 forms an end cover 25 over the bore23, the end cover having side ports 27 formed therein for transmissionof the propellant from the gun barrel 43 into the launching, orexpansion, chamber formed Within the adapter ll. The end cover 25 andside ports 27 are effective to meter a desired gas flow to a reducedpressure in the expansion chamber eiiectively formed by the spacebetween the base end of the barrel 31, base 13, and the adjacent end ofthe grenade, thereby effecting launching without burstin or rupturingthe end of the grenade, and particularly without causing pre-rupture ofthe discharge opening of the grenade, since the discharge opening islocated in the illustrated and preferred embodiment at the pressureapplication end of the grenade during launching.

The grenade adapter ll includes a barrel 31 which may be integral withthe base 13 if so desired, although in the preferred and illustratedembodiment the barrel is formed to include a separate tube which issecured at its rear end to the base 13 through the medium of securingscrews 33. The bore of the barrel Ell is rified over a longitudinalportion of its inner extent as indicated at 35 in order to accommodatethe pre-grooved rifle band formed at the base of the grenade 51, whilethe outer extent 3'7 of-the bore of the barrel 31 is smooth-walled andrecessed beneath the land surface 35:: of the rifling 35 in order toaccommodate the release handle which extends along one side of thegrenade 51 preparatory to actuation of the grenade, it being appreciatedthat the diameter of this smooth-walled extent 37 of the barrel mustalso be of sufficient size to accommodate the outer land surface 53a ofthe rified band 53 on the base end of the grenade being launched.

Referring now to FIGURE 3 the invention is particularly useful in firinga grenade having, as mentioned above, a pregrooved annular rified band53 at one end, and a release handle 55 which extends from an anchor lipformed on the opposite end and along one lateral side thereof. For mostadvantageous results the grenade may also include a striker 59 which isretained in ready position by the handle 55, preparatory to firing, asillustrated in FIGURE 3. The striker 5% is adapted to move about itspivot mounting pin under the influence of a spring 61' to strike aprimer 65 upon release of the handle 55. The handle 55 is normally heldin locked position through the medium of a safety retainer pin 63 whichmay be pulled to release the handle. However, as will be seen in FIGURE3, the smooth-walled bore extent of the barrel 31 will prevent thegrenade from being actuated until the grenade leaves the barrel 31 uponlaunching, as the handle 55 is retained in its side locking position bycontact with the smooth-walled bore extent 3? of the barrel in thepre-launching position.

The grenade 51 includes a time delay fuze 67 adjacent the primer es, anda propellant charge 69 disposed at the inner end of the time delay fuze.The entire primer, time delay fuze and propellant charge assembly ishoused in a suitable closed well or chamber 73 formed in the body of thegrenade 51. Well 73 has a blowout disc 71 formed at its bottom endadjacent the propellant charge 69, enabling the propellant gases formedby firing of the propellant charge 69 to be ejected into a chamberenclosed by the grenade canister wall and an internal movable piston 75which is adapted to thereupon move toward the opposite end of thegrenade canister and thereupon rupture blowout disc 79 and eject theparticle, liquid or gaseous material 77 which is contained in thechamber on the opposite side of the piston 75. In order to strengthenthe blowout disc 7% against rupture during the launching of the grenade,by the propellant gases from the gun 4 1, a suitable annular shoulderedcover 81 may be mounted over the recessed blowout disc 70, as forinstance by a friction fit or by pressure'sensitive tape (not shown). Itwill be appreciated that while the annular shoulder formed on the cover81 will aid in preventing rupture from external forces, the relativelylight fit of this cover over the blowout disc 79 will not materiallyimpede the ease of blowout of the disc upon actuation of the piston 75.

In operation, the operator will insert a grenade with the rifled band 53extending into the helically grooved rifled bore extent 35 of barrel 31to a seated position with the cover 81 resting on the end cover 25 ofbase 13, and with the grenade handle 55 extending within and containedby the smooth-walled bore extent 37, as shown in FIGURE 3. The operatorwill thereupon pull the safety retainer pin 63, and the handle 55 willthen be retained solely by the smoothlywalled bore extent 37. The gunand adapter assembly is then aimed in the desired direction, and uponfiring of the gun 41 the propellant gases from the firing chamber willpass through the gun barrel 43, adapter bore 23 and side ports 27 intoengagement with the rear end of the grenade 55 to thereupon eifectlaunching of the grenade from the barrel 31. The trifling 35' of thebarrel 31 will in conjunction with the pre-grooved rifled band 53 effecta desired stabilizing spin to the grenade, and upon the grenade movingforward in the barrel 31 to the point where the handle S is no longerretained by the smooth-walled bore extent 37 the handle will thereuponbe released and be ejected under the influence of the striker 59' andspring 61. The striker 59 will thereupon contact and fire the primer 65to initiate the combustion of the time delay fuze 67 and subsequentignition of the propellant charge 69 to generate the gases for ruptureof the blowout disc 71 and movement of the piston 75. Piston 75 effectscompressive action on the charge of material 77 and consequent ruptureof the blowout disc 79 and ejection of the cover 81, enabling andthereafter eflecting ejection of the charge of material 77 into theatmosphere at a desired remote zone after the grenade leaves thelauncher.

While the invention has been described as applied to a :single preferredembodiment it will be apparent that vari- 'ous modifications andimprovements may be made without departing from the scope and spirit ofthe invention. For example, in some instances where a relatively lowhelical angle may be employed in the rifled portion of the barrel 31such that a complete rotation of the grenade is not effected before thehandle 55 leaves the barrel it is possible to employ a smooth-walledbore extent 37 which will not be completely annular but will only besuificient in angular width to accommodate the necessary angularmovement of the handle 55, and in such instances the remaining portionof the bore out to the end of the barrel may be rifled. However, forpurposes of ease of manufacture and machining, as well as easing oftolerance requirements,'the presently illustrated embodiment is muchpreferred. It will accordingly be understood that the invention is notto be limited by the particular illustrative embodiment, but only by thescope of the appended claims.

That which is claimed is:

1. A grenade launcher barrel thereon of smaller be launched, comprising:

a barrel extension having a barrel portion adapted to receive a grenade,and a clamp portion,

said barrel portion having a bore therein with a first helically rifledextent and a second smooth bore extent of larger diameter than the innerland area of said rifled extent,

said smooth bore extent being at and extending inwardly from the opendischarge end of said bore and of a length adapted to accommodate aprotruding side handle on a grenade,

said clamp portion having a longitudinal bore therein for communicationbetween the bore of said barrel portion of said barrel extension and thebore of said gun barrel.

2. A grenade launcher adapter according to claim 1,

said barrel portion of said extension having a side ported coverdisposed at the input end of its bore, and

the side ports of said cover being in communication with saidlongitudinal clamp bore and said barrel portion bore.

3. A grenade launcher adapter according to claim 1 wherein said secondsmooth bore extent has a diameter at least as iarge as the diameter ofthe groove depth diameter of said rifled extent.

4. A grenade launcher adapter according to claim 1,

said clamp portion having a second bore concentric with and larger thansaid first mentioned longitudinal bore, the wall forming said secondlarger bore being adapted to fit over and abut the end of a gun barrel.

5. A grenade launcher according to claim 4,

said clamp portion forming a longitudinally split clamp having a pair oflaterally extending interfacing spaced wings for clamping adjustment ofsaid clamp portion to a barrel,

said wings each having a hole therein for receiving an adjustment screw,one of said holes being threaded and the other hole being smooth, and

an adjustment screw threadedly engaging said threaded hole.

6. A genade launcher adapter for a gun having a barrel thereon ofsmaller diameter than a grenade to be launched, comprising:

a barrel extension having a barrel portion adapted to receive a grenade,and a clamp portion,

said barrel portion having a bore therein with a helically rifled extentalong a substantial portion of the length of said bore,

said bore having a longitudinally extending smoothwalled recessedportion spaced further from the axis of said bore than the land surfacesof said rifled extent to receive a laterally protruding grenade handlewhen a grenade is loaded therein,

said smooth-walled recessed portion extending rearwardly from the openend of said bore of said barrel portion.

7. A launcher for a grenade having a laterally protruding handlecomprising:

a gun having a grenade holding and launching section with agrenadereceiving bore therein,

said grenade holding and launching section bore includ ing a helicallyrifled extent,

and said bore having a longitudinally extending smoothwalled recessedportion adjacent said rifled extent and spaced further from the axis ofsaid bore than the land surfaces of said rifled extent to receive alaterally protruding grenade handle when a grenade is loaded therein,said smooth-walled recessed portion extending rearwardly from the openend of said bore of said barrel portion.

adapter for a gun having a diameter than a grenade to 8. A launcher fora grenade according to claim 7,

said smooth-walled recessed portion extending through the full annularextent of said bore.

9. The arrangement according to claim 7 further comprising:

a grenade having an explosive charge, charge-igniting device, and arelease handle for enabling operation of said charge-igniting device,said release handle protruding laterally along a longitudinal extent ofsaid grenade, and a rifled band extending about a portion of the body ofsaid grenade at a position longitudinally spaced from said handle,

said grenade release handle fitting into said smoothwalled recessedportion of said barrel arrangement bore in a position preventing releaseof said handle and charge-igniting device, and

said rifled band fitting into said helically rifled extent.

16. The arrangement according to claim 9, said chargeigniting deviceincluding a combustible time delay unit for igniting said charge, apercussion primer for igniting said combustible time delay unit, and aspring biased striker adapted to move said release handle to releaseposition after movement of said handle beyond the open end of said boreand to eflect impact firing of said percussion primer thereupon, wherebysaid explosive charge will thereafter be ignited by said time delay unitat a predetermined time after launching of said grenade.

No references cited.

BENJAMIN A. BORCHELT, Primary Examiner.

1. A GRENADE LAUNCHER ADAPTER FOR A GUN HAVING A BARREL THEREON OFSMALLER DIAMETER THAN A GRENADE TO BE LAUNCHED, COMPRISING: A BARRELEXTENSION HAVING A BARREL PORTION ADAPTED TO RECEIVE A GRENADE, AND ACLAMP PORTION, SAID BARREL PORTION HAVING A BORE THEREIN WITH A FIRSTHELICALLY RIFLED EXTENT AND A SECOND SMOOTH BORE EXTENT OF LARGERDIAMETER THAN THE INNER LAND AREA OF SAID RIFLED EXTENT, SAID SMOOTHBORE EXTENT BEING AT AND EXTENDING INWARDLY FROM THE OPEN DISCHARGE ENDOF SAID BORE AND OF A LENGTH ADAPTED TO ACCOMMODATE A PROTRUDING SIDEHANDLE ON A GRENADE, SAID CLAMP PORTION HAVING A LONGITUDINAL BORETHEREIN FOR COMMUNICATION BETWEEN THE BORE OF SAID BARREL PORTION OFSAID BARREL EXTENSION AND THE BORE OF SAID GUN BARREL.